# Python实现下载文件的三种方法
# 方法一：

import urllib 

print "downloading with urllib"
url = 'http://www.jb51.net//test/demo.zip'
urllib.urlretrieve(url, "demo.zip")

# 方法二：


import urllib2

print "downloading with urllib2"
url = 'http://www.jb51.net//test/demo.zip'
f = urllib2.urlopen(url) 
data = f.read() 
with open("demo2.zip", "wb") as code: 
code.write(data)

# 方法三：


import requests 

print "downloading with requests"
url = 'http://www.jb51.net/test/demo.zip'
r = requests.get(url) 
with open("demo3.zip", "wb") as code:
code.write(r.content)

# 看起来使用urllib最为简单，一句语句即可。当然你可以把urllib2缩写成：

f = urllib2.urlopen(url) 
with open("demo2.zip", "wb") as code:
code.write(f.read())
 